Seems like a solid start to a mystery-dungeon style game! I remember trying to build something like this long ago (back when I actually typed code...) but I never got very far.
I played until floor 12, and stopped there. It probably wouldn't take to much more to make this a full game. Enemies, items, maybe some traps. Obviously that's all easier said than done, but I think you've made a good start!
When I was making this I had some kind of story in mind that this is a boy that found himself in a lab when waking up (hence why the stairs go up instead of down)
Adding enemies items and traps will definitely turn this into a standard roguelike; tho making games of this kind (or any game really) the devil is in the polish ^^
...for example idk if you notice, but the maze's size (therefore also difficulty and complexity) increases every five level both horizontally and vertically (at start the maze is at least 5×5 and max 8×8 at level 6 it's 6~9). When I tested it myself the maze becomes sooo hellish after it expanded twice, which is for lvl 11-15 -- and in levels 16-20 there are levels that I spent wandering around for 10min lol
The maze size definitely can't just increase quadratically every 5 lvls like this lol
